function Tab(el){
    this.el=document.querySelector(el)
    this.init()
}
Tab.prototype.init=function(){
    // 鼠标移入
    this.mouseOver()
}
Tab.prototype.mouseOver=function(){
    let ulLiObj=this.el.querySelectorAll('ul li')
    ulLiObj.forEach((item,i) => {
        item.onmouseover=()=>{
            this.tbTitle(ulLiObj, i)
            this.tbContent(i)
        }
    })
}
Tab.prototype.tbTitle=function(ulLiObj, i){
    this.el.querySelector('ul li.active').className=''
    ulLiObj[i].className='active'

    }


Tab.prototype.tbContent=function(i){
this.el.querySelector('ol li.active').className=''
let olLiObject=this.el.querySelectorAll('ol li')
olLiObject[i].className='active'

}